This invention enables a vacuum cleaner to use flexible bags as disposable liners for the refuse compartment of the cleaner, similar to the common use of thin-film plastic bags as disposable liners for trash containers. The problem with using such a liner directly in a vacuum cleaner is that the liner or the refuse inside tends to be drawn into the vacuum pump or other parts of the cleaner during operation.
There have been various attempts by other manufacturers to secure such liners inside the refuse compartments so that neither the liners nor their contents are drawn into other parts of the cleaner. Such attempts have included external pressure-equalization tubes, bag weights, reusable magnets, and clips that attach to the bottom of the liner. These attempts have proven to be expensive or inconvenient for the operator of the vacuum. If the operator forgets or otherwise fails to properly attach the liner just one time, the cleaner can be damaged.
A more convenient attempt to hold the liner in place is shown in Lubraniecki, U.S. Pat. No. 4,811,453. This method involves creating a difference in air pressure between the inside and outside of the liner so that the liner is drawn outwards and held in place against porous walls of the refuse compartment. The pressure difference is created by forcing the air used in the cleaning process to flow through a filter, such as the porous filters used in many vacuum cleaners to separate dirt from the air stream. This method requires that the connection to the liner be sealed and that the liner itself be non-porous so that air cannot bypass the filter. It also requires a double wall for the dirt compartment, including a porous inside wall to support the liner. In addition, air ducts are required to connect the liner and the double wall to the filter.
This method suffers from the added expense required for making the more complex refuse compartment and from the problematic clogging of the double wall that can result from a break in the liner or from omitting the liner even one time. The added expense is particularly a problem for vacuum cleaners that use cyclonic dirt separators since an extra filter must be added for this method. In addition, the operator must employ extra care to be sure that the bag seals properly in order for the method to work.
Consequently, there is a need for an inexpensive method of securing a liner inside the refuse compartment of a vacuum cleaner in a manner that is as convenient as placing a liner in a regular trash container and in a manner that will not damage the cleaner in case that the liner breaks or that the liner is not positioned correctly.